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What are disasters? It's hard to tell precisely when a hazard becomes a disaster D Vulnerable but dregs model shows the overlap required before a hazard Hazardous I population: S becomes a disaster. It's a matter of scale, a disaster is geophysic- A human and S economic bigger than a hazard. Some insurance companies have tried al event. T loss, due to to define it as a loss of more than 20 loves and an economic E location. R loss of over $16million.One factor as to whether it has become a disaster or not depends on how vulnerable thepopulation is.Vulnerability: High risk combined with an inability of individuals to cope. Location Lack of accessibility Low Poverty capacity High population density to cope. Urban migration due to population increase.Risk: The probability of a hazard event occurringand creating loss of lives.Hazards to people (death + disease) Risk = Frequency/Magnitude x level of vulnerabilityHazards to goods (economic loss) Capacity to copeHazards to environment (pollution)…read more

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Why do people remain at risk from hazards & disasters?Changing risks ­ It's difficult to predict where or when an event may occur andthe impact it will have. They vary in space as well as time due to changing humanactivities and physical factors such as tectonic plate movement. Places once safe tolive are now in danger due to rising sea levels, deforestation and other changes.Lack of alternatives ­ Often the most vulnerable people are the poorest and areforced to live in unsafe places due to lack of knowledge or better alternatives.Benefits vs costs ­ Benefits include fertile farming land, which may outweigh therisks from it.Risk perception ­ People are comforted by statistics which show the risk of deathfrom a hazard as very low and believe it won't happen in their life time.An ageing population - Older people (65+) are the least mobile in a communityand have less capacity to take action either before or after a natural disaster.Dependence on technology - Our belief that we are able to predict and control thenatural environment and its processes has led us to develop areas for humanhabitation which previously may not have been considered safe or viable. Also we're more dependent on systems of water, power, communication and transport thanever before. When these systems collapse under the onslaught of a natural hazard,we are unable to fend for ourselves.…read more

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Global Hazard Trends (how & why are natural hazards an increasing threat?) Global disaster trends - Natural disasters are more common in countries with a low and medium level of development. Many of these countries are in tropical areas which have monsoon rainfall or hurricanes. Disasters cause more death and disruption in poor countries, which lack the resources and funds to develop high-tech prevention and prediction systems. Damage in absolute economic terms remains highest in high-income countries but in relative terms it is much more devastating for poorer countries. Interpreting statistics - Reported by governments. Validity is questioned for number of reasons:1)No universal definition of disaster so therefore it's down to each persons interpretation2)When reporting deaths, it depends on whether deaths from both primary & secondary disasters are reported or just primary.3)Depending on location disasters go unreported.4)Declaration of deaths may be subject to political influences, perhaps to make money.5)Complex to collect depending on location and accuracy of existing statistics.6)Time trend analysis (trends over time) can be difficult depending on the intervals. Analysis of hazard trends ­ The number of reported statistics has risen significantly in recent year perhaps due to growing media as well as increasing number of vulnerable people. Since 1960's hydro-meteorological have rising dramatically, geophysical have had no overall rising and biological slow slight rise from 1990's onwards.…read more

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Magnitude and frequency ­ Magnitude (size of natural hazard. Represents energy given offduring event). Magnitude scales categorise events according to size/energy. Scales include:Hurricanes: Saffir-Simpson scale (1-5)Earthquakes: Richer Scale (1-10 log scale)Tornadoes: TORRO or Fujita intensity scalesVolcanic eruptions: explosivity indexLower magnitude events, such as an earth tremor of Richter Scale 2.5, have less than high-magnitude events, such as the 2004 earthquake measuring 9.1 on the Richter Scale.Frequency (number of events of given magnitude which occur over time). Low magnitudeevents are likely to have a more frequency recurrence level, and present more frequent butless devastating risks.Contrasting trends - Geophysical hazards show fluctuations over time which can beaccounted for by the clustering of events along mobile plate boundaries. There have been anumber of earthquakes off the coast of Indonesia, where the Indian plate is being subductedbeneath the Burma plate. However, there is no solid evidence that the frequency/magnitudeof hazards is increasing. In contrast number of reported hydro-meteorological events isincreasing, likely to be associated with climate change, with predictions that global warmingwill increase frequency, magnitude & impact of the disasters. Another explanation ofincreased frequency lies in the context hazard of increased environmental degradationcaused by population pressure such as deforestation leading to flash flooding. We cannot besure that damage to environment causes disasters, but it's clear that it impacts on them.…read more